From 17b74b98676aee5bc470b173b1e528d2fce2cf18 Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Wed, 4 May 2016 18:49:17 +0200 Subject: migration: Move qjson.[ch] to migration/ Type QJSON lets you build JSON text. Its interface mirrors (a subset of) abstract JSON syntax. QAPI output visitors also produce JSON text. They assert their preconditions and invariants, and therefore abort on incorrect use. Contrastingly, QJSON does *not* detect incorrect use. It happily produces invalid JSON then. This is what migration wants. QJSON was designed for migration, and migration is its only user. Move it to migration/ for proper coverage by MAINTAINERS, and to deter accidental use outside migration. [Pointed out by Eric: QJSON was added in commits 0457d07..b174257 -- Amit] Signed-off-by: Markus Armbruster Reviewed-by: Eric Blake Reviewed-by: Dr. David Alan Gilbert Message-Id: <1462380558-2030-2-git-send-email-armbru@redhat.com> Signed-off-by: Amit Shah --- include/migration/qjson.h | 29 +++++++++++++++++++++++++++++ include/migration/vmstate.h | 2 +- include/qjson.h | 29 ----------------------------- 3 files changed, 30 insertions(+), 30 deletions(-) create mode 100644 include/migration/qjson.h delete mode 100644 include/qjson.h (limited to 'include') diff --git a/include/migration/qjson.h b/include/migration/qjson.h new file mode 100644 index 0000000000..7c54fdf0ac --- /dev/null +++ b/include/migration/qjson.h @@ -0,0 +1,29 @@ +/* + * QEMU JSON writer + * + * Copyright Alexander Graf + * + * Authors: + * Alexander Graf + * + * This work is licensed under the terms of the GNU LGPL, version 2.1 or later. + * See the COPYING.LIB file in the top-level directory. + * + */ +#ifndef QEMU_QJSON_H +#define QEMU_QJSON_H + +#define TYPE_QJSON "QJSON" +typedef struct QJSON QJSON; + +QJSON *qjson_new(void); +void json_prop_str(QJSON *json, const char *name, const char *str); +void json_prop_int(QJSON *json, const char *name, int64_t val); +void json_end_array(QJSON *json); +void json_start_array(QJSON *json, const char *name); +void json_end_object(QJSON *json); +void json_start_object(QJSON *json, const char *name); +const char *qjson_get_str(QJSON *json); +void qjson_finish(QJSON *json); + +#endif /* QEMU_QJSON_H */ diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h index 84ee355ceb..30ecc441de 100644 --- a/include/migration/vmstate.h +++ b/include/migration/vmstate.h @@ -29,7 +29,7 @@ #ifndef CONFIG_USER_ONLY #include #endif -#include +#include "migration/qjson.h" typedef void SaveStateHandler(QEMUFile *f, void *opaque); typedef int LoadStateHandler(QEMUFile *f, void *opaque, int version_id); diff --git a/include/qjson.h b/include/qjson.h deleted file mode 100644 index 7c54fdf0ac..0000000000 --- a/include/qjson.h +++ /dev/null @@ -1,29 +0,0 @@ -/* - * QEMU JSON writer - * - * Copyright Alexander Graf - * - * Authors: - * Alexander Graf - * - * This work is licensed under the terms of the GNU LGPL, version 2.1 or later. - * See the COPYING.LIB file in the top-level directory. - * - */ -#ifndef QEMU_QJSON_H -#define QEMU_QJSON_H - -#define TYPE_QJSON "QJSON" -typedef struct QJSON QJSON; - -QJSON *qjson_new(void); -void json_prop_str(QJSON *json, const char *name, const char *str); -void json_prop_int(QJSON *json, const char *name, int64_t val); -void json_end_array(QJSON *json); -void json_start_array(QJSON *json, const char *name); -void json_end_object(QJSON *json); -void json_start_object(QJSON *json, const char *name); -const char *qjson_get_str(QJSON *json); -void qjson_finish(QJSON *json); - -#endif /* QEMU_QJSON_H */ -- cgit v1.2.3-55-g7522 From b72fe9e690db5082fdd0476074230cf2c65508bf Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Wed, 4 May 2016 18:49:18 +0200 Subject: migration/qjson: Drop gratuitous use of QOM All the use of QOM buys us here is the ability to destroy the thing with object_unref(OBJECT(vmdesc)). Not worth the notational overhead. Signed-off-by: Markus Armbruster Reviewed-by: Eric Blake Reviewed-by: Dr. David Alan Gilbert Message-Id: <1462380558-2030-3-git-send-email-armbru@redhat.com> Signed-off-by: Amit Shah --- include/migration/qjson.h | 2 +- migration/qjson.c | 39 ++++++--------------------------------- migration/savevm.c | 2 +- 3 files changed, 8 insertions(+), 35 deletions(-) (limited to 'include') diff --git a/include/migration/qjson.h b/include/migration/qjson.h index 7c54fdf0ac..2978b5f371 100644 --- a/include/migration/qjson.h +++ b/include/migration/qjson.h @@ -13,10 +13,10 @@ #ifndef QEMU_QJSON_H #define QEMU_QJSON_H -#define TYPE_QJSON "QJSON" typedef struct QJSON QJSON; QJSON *qjson_new(void); +void qjson_destroy(QJSON *json); void json_prop_str(QJSON *json, const char *name, const char *str); void json_prop_int(QJSON *json, const char *name, int64_t val); void json_end_array(QJSON *json); diff --git a/migration/qjson.c b/migration/qjson.c index cb479fe0eb..5cae55af07 100644 --- a/migration/qjson.c +++ b/migration/qjson.c @@ -26,17 +26,12 @@ #include "qemu/osdep.h" #include "qapi/qmp/qstring.h" #include "migration/qjson.h" -#include "qemu/module.h" -#include "qom/object.h" struct QJSON { - Object obj; QString *str; bool omit_comma; }; -#define QJSON(obj) OBJECT_CHECK(QJSON, (obj), TYPE_QJSON) - static void json_emit_element(QJSON *json, const char *name) { /* Check whether we need to print a , before an element */ @@ -100,41 +95,19 @@ const char *qjson_get_str(QJSON *json) QJSON *qjson_new(void) { - QJSON *json = QJSON(object_new(TYPE_QJSON)); - return json; -} - -void qjson_finish(QJSON *json) -{ - json_end_object(json); -} - -static void qjson_initfn(Object *obj) -{ - QJSON *json = QJSON(obj); + QJSON *json = g_new0(QJSON, 1); json->str = qstring_from_str("{ "); json->omit_comma = true; + return json; } -static void qjson_finalizefn(Object *obj) +void qjson_finish(QJSON *json) { - QJSON *json = QJSON(obj); - - qobject_decref(QOBJECT(json->str)); + json_end_object(json); } -static const TypeInfo qjson_type_info = { - .name = TYPE_QJSON, - .parent = TYPE_OBJECT, - .instance_size = sizeof(QJSON), - .instance_init = qjson_initfn, - .instance_finalize = qjson_finalizefn, -}; - -static void qjson_register_types(void) +void qjson_destroy(QJSON *json) { - type_register_static(&qjson_type_info); + g_free(json); } - -type_init(qjson_register_types) diff --git a/migration/savevm.c b/migration/savevm.c index bfb3d9178f..8546fdfae1 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -1115,7 +1115,7 @@ void qemu_savevm_state_complete_precopy(QEMUFile *f, bool iterable_only) qemu_put_be32(f, vmdesc_len); qemu_put_buffer(f, (uint8_t *)qjson_get_str(vmdesc), vmdesc_len); } - object_unref(OBJECT(vmdesc)); + qjson_destroy(vmdesc); qemu_fflush(f); } -- cgit v1.2.3-55-g7522 From 24f3902b088cd4f2dbebfd90527b5d81d6a050e9 Mon Sep 17 00:00:00 2001 From: Greg Kurz Date: Wed, 4 May 2016 21:44:19 +0200 Subject: savevm: fail if migration blockers are present QEMU has currently two ways to prevent migration to occur: - migration blocker when it depends on runtime state - VMStateDescription.unmigratable when migration is not supported at all This patch gathers all the logic into a single function to be called from both the savevm and the migrate paths. This fixes a bug with 9p, at least, where savevm would succeed and the following would happen in the guest after loadvm: $ ls /host ls: cannot access /host: Protocol error With this patch: (qemu) savevm foo Migration is disabled when VirtFS export path '/' is mounted in the guest using mount_tag 'host' Signed-off-by: Greg Kurz Reviewed-by: Paolo Bonzini Message-Id: <146239057139.11271.9011797645454781543.stgit@bahia.huguette.org> [Update subject according to Paolo's suggestion - Amit] Signed-off-by: Amit Shah --- include/migration/migration.h | 1 + migration/migration.c | 21 +++++++++++++++------ migration/savevm.c | 2 +- 3 files changed, 17 insertions(+), 7 deletions(-) (limited to 'include') diff --git a/include/migration/migration.h b/include/migration/migration.h index ac2c12c2a5..9e36a97fc5 100644 --- a/include/migration/migration.h +++ b/include/migration/migration.h @@ -210,6 +210,7 @@ int migrate_fd_close(MigrationState *s); void add_migration_state_change_notifier(Notifier *notify); void remove_migration_state_change_notifier(Notifier *notify); MigrationState *migrate_init(const MigrationParams *params); +bool migration_is_blocked(Error **errp); bool migration_in_setup(MigrationState *); bool migration_has_finished(MigrationState *); bool migration_has_failed(MigrationState *); diff --git a/migration/migration.c b/migration/migration.c index 12dbf5b343..721d010fde 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -992,6 +992,20 @@ void qmp_migrate_incoming(const char *uri, Error **errp) once = false; } +bool migration_is_blocked(Error **errp) +{ + if (qemu_savevm_state_blocked(errp)) { + return true; + } + + if (migration_blockers) { + *errp = error_copy(migration_blockers->data); + return true; + } + + return false; +} + void qmp_migrate(const char *uri, bool has_blk, bool blk, bool has_inc, bool inc, bool has_detach, bool detach, Error **errp) @@ -1014,12 +1028,7 @@ void qmp_migrate(const char *uri, bool has_blk, bool blk, return; } - if (qemu_savevm_state_blocked(errp)) { - return; - } - - if (migration_blockers) { - *errp = error_copy(migration_blockers->data); + if (migration_is_blocked(errp)) { return; } diff --git a/migration/savevm.c b/migration/savevm.c index 8546fdfae1..f8450fd0e9 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -1170,7 +1170,7 @@ static int qemu_savevm_state(QEMUFile *f, Error **errp) MigrationState *ms = migrate_init(¶ms); ms->to_dst_file = f; - if (qemu_savevm_state_blocked(errp)) { + if (migration_is_blocked(errp)) { return -EINVAL; } -- cgit v1.2.3-55-g7522